This proposal requests funds to enable scientists, particularly young investigators, to attend the 12th International Herpesvirus Workshop at the University of Pennsylvania, Philadelphia, PA, July 30August 4, 1987. The importance of this workshop rests on the diverse aspects of human and animal herpesvirus biology presented, strong support and participation of leading researchers and students, and broadbased international attendance. Participants include specialists in molecular biology, immunology, pathogenesis, latency, clinical investigations, epidemiology, treatment and prevention. Many presentations concern the human herpesviruses, universally prevalent in all populations, persist for life, and cause significant diseases. All human herpes virus infections are a major problem in immunosuppressed patients, i.e, cancer, transplant and AIDS. Several herpeviruses are implicated in human neoplasia. For example, EpsteinBarr virus is linked with nasopharyngeal carcinaoma and Burkitt's lymphoma. Herpes simplex type 1 (HSV1) causes blindness and encephalltis, and is a major hazard of dental practice. HSV2 is a leading cause of venereal disease and is linked to cervical carcinoma. Congenital cytomegalovirus infections are a major cause of birth defects. There is increasing interest in animal herpesviruses which have significant economic importance, cause diseases analogous to those caused by human herpesviruses, and provide information on effectiveness of vaccines in the natural host. At least two animal herpesviruses cause nipplasis and serve as models for human nioplasia. A novel herpes virus, human Blymphotropic virus (HBLV) was very recently isolated from patients with lymphoproliferative disorders. In two instances, HBLV was associated with HTVLIII/LAV seropositive donors. We expect there to be much excitement and many new developments to be reported on this important new herpesvirus at the next Workshop. Workshop organizers are Dr. R. J. Eisenberg, School of Veterinary Medicine, and Dr. G. H. Cohen, School of Dental Medicine, University of Pennsylvania. The topics are: gene expression, DNA replication, genome structure and virus assembly, transformation and neoplasia, antivirals and vaccines, immunology, latency and pathogenesis, enzymes and other nonstructural proteins, glycoproteins and structural proteins.